Chemistry Lab Chemistry Lab

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Chemistry Lab Chemistry Lab Powered By Docstoc
					Chemistry Lab
 By Lin Wozniewski
   lwoz@iun.edu
What do they need to be able to do
     every year every year?
 Interpretation of          Nomenclature and
 experimental data          formula writing - symbols
 (tabular and/or graphic)   and charges for the
                            following ions by memory:
 Observation of an          nitrate, carbonate,
 experiment set up and      phosphate, acetate,
 running                    sulfate, ammonium,
                            bicarbonate, and
                            hydroxide (“ite” forms of
 Computer or calculator     “ates” listed)
 sensors/probes

  Stoichiometry : mole
 conversions and
 percentage yield
                   Safety
Students must wear:
   Closed shoes
   Slacks or skirts that come to the ankles
   Sleeved Shirt (if wearing a lab apron)
   Lab coat or lab apron
   Indirect vent or unvented chemical splash
    proof goggles. No impact glasses or
    visorgogs are permitted
 What the Students Should Bring
   Safety gear
   Something to write with


What the Students Should Not Bring

    Anything else
    This includes notes
What the Supervisor Provides
Everything the student will need
  How to prepare participants
Make sure students read the directions and pay
particular attention to the description of the event
(The Competition)

Have them do many experiments together

Have them determine their individual strengths

Divide (and conquer) tasks during competition

Check each other’s work
 How to prepare participants
Get as many lab books from your
chemistry teacher as possible & have
students explore labs by topic and do the
ones that appear consistently
          Changes for 2009
2 new topics:
   Kinetics
   Aqueous Solutions
                  Kinetics
Students will demonstrate an understanding of
  the principals of kinetics. They must be able
  to measure reaction rates and identify how
  and why reaction conditions (temperature,
  concentration, particle size, and catalysts)
  affect reaction rates. At the regional level,
  teams will NOT be asked to determine rate
  laws experimentally or from data provided.
  At the state and national levels, teams will be
  asked to determine rate laws from actual
  experimentation or data provided, and teams
  should also be able to determine rate
  constants with correct units
                    Kinetics
Calculating a rate
   Fair game at Regional Competitions
            [limitingreagent]
     Rate 
                   time
   [] means the concentration of
Rate Law
   Can only be done at State and National
   Rate = k[A]x[B]y…
         Kinetic Activities
Iodine Clock Reaction – one of the most
famous & widely used kinetic reactions
Very easy to do, but very hard to explain
all of the chemistry
http://jchemed.chem.wisc.edu/JCESoft/CC
A/CCA3/MAIN/CLOCKRX/PAGE1.HTM
For a really cool oscillating reaction (if you
have the resources)
http://chemistry.about.com/cs/demonstrati
ons/a/aa050204a.htm
         Kinetic Activities

To see the effects of surface area
Reaction of Powdered Sugar and Granular
Sugar with concentrated H2SO4
http://www.exo.net/~pauld/activities/astron
omy/transitvenus/sugarsulfuricacid.htm
        Kinetic Activities
To see the effects of concentration on
kinetics, try
Reaction of mossy zinc in 2 M CuSO4 & .2
M CuSO4
             Kinetics Activities
To see the effect of temperature, try a simple
baking soda and vinegar experiment at different
temperatures.
   Place 20 ml of vinegar in 100 ml graduated cylinder
   Add 1 drop dish soap
   Place 1 g baking soda in a separate beaker.
   Add 25 ml water & dissolve
   Pour 20 ml of baking soda in vinegar and start
    timing as soon as solutions hit each other
   Time how long it takes for suds to reach top of
    cylinder
   Increase or decrease temperature of one or the
    other reagent
        Kinetics Activities
http://chemistry.about.com/od/stoichiometr
y/a/reactionrate.htm
          Aqueous Solutions
Students will demonstrate an understanding of the
principals and properties of aqueous solutions.
They must be able to calculate solution
concentrations given quantities of solute and
solvent, and to calculate quantities of material
required to produce a solution of specified
concentration. Molarity, molality, mass
percentage, and parts per million may be required.
Students are also required to demonstrate an
understanding of colligative properties. At the
state and national levels, conversions between
concentration units may be required.
         Aqueous Activities
Use the concept of density to experimentally
determine the concentration of a solution.
Determine solution concentration using a series of
standard absorbencies and Beer’s Law.
Use freezing point depression to determine the
molar mass of a solute.
Use titration to determine an unknown concentration.
Identify and explain factors that effect solution
formation.
Construct a solubility curve.
Determine whether a solution is saturated,
unsaturated or supersaturated
       Aqueous Activities
http://chemtutor.com/mols.htm#dv
http://web.archive.org/web/200705050057
26/library.thinkquest.org/10429/low/sol/sol.
htm
Resources: TI Activity Exchange
http://education.ti.com/educationportal/acti
vityexchange/BrowseResult.do?cid=US&s
ubName=Science&subAreaName=Chemis
try&subAreaId=5028&catName=Kinetics&
catId=1097&aCount=6&brsOpenNode=bt1
.o%2816%29
             Scoring
50% Kinetics
50% Aqueous Solutions
Questions???
  Thank you